5.1 Structural Loads & Systems

PRC Architect Licensure Examination ALE

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1 Introduction

About the PRC Architect Licensure Examination (ALE) How the ALE Is Organized & Scored

2 Chapter 1: Philippine & World Architectural History

1.1 Pre-Colonial & Spanish Colonial Philippine Architecture 1.2 American Colonial Period, Filipino Modernism & National Artists for Architecture 1.3 World Architectural History: Classical Through Modern Movements

3 Chapter 2: Architectural Theory & Planning Principles

2.1 Architectural Theories & Design Philosophies 2.2 Urban & Regional Planning Principles 2.3 Environmental Psychology & Human Behavior in Design

4 Chapter 3: RA 9266 and the Legal Framework of Practice

3.1 RA 9266: The Architecture Act of 2004 3.2 The PRBoA, Licensure & Scope of Practice 3.3 Code of Ethical Conduct for Architects

5 Chapter 4: Professional Practice, Contracts & UAP Standards

4.1 UAP Standards of Professional Practice (SPP Documents) 4.2 Contract Documents, Delivery Methods & Specifications 4.3 Professional Liability, Insurance & Construction Administration

6 Chapter 5: Structural Conceptualization & Systems

5.1 Structural Loads & Systems 5.2 Seismic Design Principles & the NSCP (Seismic Zone 4) 5.3 Structural Materials: Concrete, Steel, Timber & Masonry

7 Chapter 6: Building Materials & Construction Methods

6.1 Building Materials & Specifications 6.2 Construction Methods, Sequencing, QC & Safety 6.3 Building Envelope: Waterproofing, Doors, Windows & Roofing

8 Chapter 7: Building Utilities

7.1 Plumbing & Sanitary Systems 7.2 Electrical Systems & Illumination Design 7.3 HVAC, Mechanical Systems & Acoustics

9 Chapter 8: PD 1096 — The National Building Code

8.1 PD 1096 Development Controls: PSO, TGFA, FLAR & Setbacks 8.2 PD 1096 Fire Safety, Light, Ventilation & Occupancy 8.3 Applying PD 1096: Worked Examples & Common Exam Traps

10 Chapter 9: Site Analysis & Climate-Responsive Design

9.1 Site Analysis: Topography, Environmental Factors & Context 9.2 Tropical Climate-Responsive Design 9.3 Sustainable & Green Design Principles

11 Chapter 10: Programming & Space Planning

10.1 Space Programming & Functional Relationships 10.2 Circulation Systems & Spatial Organization 10.3 Building Typologies & User Requirements

12 Chapter 11: Zoning, Development Controls & Accessibility

11.1 Zoning Regulations, Setbacks & Site Development 11.2 BP 344 Accessibility Law & Universal Design 11.3 Life Safety, Egress & Fire-Code Compliance in Design

13 Chapter 12: Urban Design & Site Planning Process

12.1 Urban Design Principles & Site Development Concepts 12.2 Site Planning Process: From Analysis to Concept 12.3 Landscape Architecture & Site Development Elements

14 Chapter 13: Architectural Graphics, Presentation & Design Exam Strategy

13.1 Architectural Graphics: Plans, Sections, Elevations & Scales 13.2 Presentation Techniques & Design Communication 13.3 The ALE Design Exam Format: Problem-Solving Approach 13.4 Design Strategy & Time Management

5.1 Structural Loads & Systems

Key Takeaways Explain This Topic AI

NSCP Table 205-1 sets minimum uniform live loads by occupancy: 1.9 kPa for residential floor areas, 2.4 kPa for offices, and 4.8 kPa for ground-floor corridors and lobbies.

Seismic load scales with a building's mass (an inertial effect), while wind load scales with its exposed surface area and shape - a critical conceptual distinction on the exam.

Five architectural-scale structural systems recur on the ALE: post-and-beam frames, bearing walls, shear walls, moment-resisting frames, and long-span systems such as trusses or space frames.

A 'discontinuous load path' - a shear wall or column that does not run in an unbroken vertical line from roof to foundation - is a schematic-stage design flaw the architect, not only the engineer, must catch.

Last updated: July 2026

Understanding Structural Loads

On the ALE, the Structural Design, Building Materials & Methods of Construction, and Utilities subject does not ask candidates to run structural calculations - that is the domain of the licensed civil/structural engineer. Instead, PRBoA expects an architect to understand load types well enough to conceptually coordinate a structural system into a design at the schematic stage, long before an engineer is engaged. Every building must be designed to safely resist four fundamental categories of load.

Dead Loads

Dead loads are permanent, unchanging loads: the self-weight of the structure itself (columns, beams, slabs, walls) plus permanently attached elements such as roofing, ceilings, fixed partitions, and built-in mechanical equipment. Dead load is calculated from the unit weights of the actual materials used and does not change over the building's life unless the architect specifies new permanent finishes or fixed equipment - for example, retrofitting a heavy garden roof onto an existing structure adds dead load that the original structure may not have been designed to carry.

Live Loads

Live loads are variable, movable loads generated by occupancy: people, furniture, storage, and movable equipment. The National Structural Code of the Philippines (NSCP) sets minimum uniform live loads by occupancy type in Table 205-1. Selected values:

• Occupancy Minimum Uniform Live Load (NSCP Table 205-1)
• Residential (basic floor areas) 1.9 kPa
• Offices 2.4 kPa
• Corridors above the ground floor 3.8 kPa
• Ground-floor corridors and lobbies 4.8 kPa

Notice that ground-floor corridors and lobbies carry a higher minimum live load than upper-floor corridors, because ground-floor circulation spaces see denser, less predictable crowd loading. An architect who programs a heavier-occupancy use (an assembly hall, a library stack room, a storage mezzanine) into a space designed for light residential live load is proposing a structural mismatch that must be flagged and coordinated with the engineer.

Wind Loads

The Philippines sits in one of the most typhoon-exposed regions on Earth , and wind loads are lateral (and sometimes uplift) forces that act on a building's exposed surface area. Wind load design is critical for tall or slender buildings (lateral sway) and for lightweight roof systems, where uplift - wind lifting the roof rather than pushing it down - is a common failure mode in typhoon-damaged Philippine buildings. Architects influence wind performance directly through building shape, roof pitch and overhang design, and tie-down detailing at roof-to-wall connections.

Seismic Loads

Seismic (earthquake) loads are lateral forces generated not by wind pressure on a surface, but by the building's own mass resisting sudden ground acceleration - an inertial effect. This is a critical conceptual distinction the ALE tests: wind load is roughly proportional to a building's exposed surface area and shape, while seismic load is roughly proportional to the building's mass . A heavier building of the same footprint (for example, a solid concrete structure versus a lightweight steel one) attracts significantly greater seismic force. Section 5.2 covers seismic design in the Philippine context in depth.

Structural Systems for Architectural Design

Architects conceptually select a structural system based on building type, required span, and loading , coordinating that choice with the design's spatial and aesthetic intent from the earliest schematic sketches.

System How It Works Best Suited For

Post-and-beam (frame) Columns and beams carry loads through bending and axial action, leaving open floor plans Most Philippine mid-rise reinforced concrete (RC) buildings; flexible layouts

Bearing wall Solid walls carry vertical loads directly in compression Low-rise, repetitive-plan buildings: housing, dormitories, hotels

Shear wall Rigid vertical planar walls resist lateral (wind/seismic) forces Paired with a gravity frame; commonly placed at stair/elevator cores

Moment-resisting frame (MRF) Rigid beam-column connections resist lateral load through bending, without walls or bracing Open glazed facades; ductile seismic detailing

Long-span systems (trusses, space frames, shells) Distribute load across large clear spans Gymnasiums, terminals, warehouses, churches, atriums

A post-and-beam (frame) system is the default choice for most Philippine commercial and residential mid-rise construction because it keeps floor plans open and flexible. A bearing wall system is efficient where the plan repeats floor after floor (a dormitory or budget hotel), but walls must align vertically from floor to floor, and the system loses flexibility if the architect later wants to remove or relocate a wall. A shear wall system is rarely used alone for gravity support; it is added specifically to resist lateral force, and Philippine designers frequently concentrate shear walls at the stair and elevator core, which lets the rest of the floor plate stay open while still giving the building an efficient lateral system. A moment-resisting frame trades larger, more heavily reinforced beam-column joints for the freedom to skip walls and bracing entirely, which is why it is popular for lobbies and glazed ground floors. Long-span systems are selected whenever a program needs a large column-free volume; as a rule of thumb, a truss's structural depth runs roughly 1/10 to 1/15 of its span, and the architect must reserve that depth in the section from the earliest massing study, not after the design is finalized.

Load Path: How Loads Reach the Ground

Every load - dead, live, wind, or seismic - must travel along a continuous, unbroken load path from where it originates to the ground: roof loads travel through roof framing into supporting walls or columns, floor loads repeat this pattern at every level, and all accumulated loads ultimately reach the foundation , which distributes them to the soil at a pressure the soil can safely bear. A discontinuous load path - for instance, a shear wall or column that does not continue in an unbroken vertical line from roof to foundation, but instead 'floats' onto a beam or transfer slab - creates a dangerous concentration of force at the transfer point. Recognizing and eliminating discontinuous load paths at the schematic design stage, before the structural engineer is engaged, is one of the most important structural responsibilities the ALE expects of a licensed architect.